Outcomes of Radiation Therapy Plus Immunotherapy in Metastatic Renal Cell Carcinoma: Results From the Canadian Kidney Cancer Information System

Purpose

With the integration of immunotherapy (IO) agents in the management of metastatic renal cell carcinoma (mRCC), there has been interest in the combined use with radiation therapy (RT). However, real world data are limited. The purpose of this study was to evaluate outcomes in patients with mRCC receiving both RT and IO compared with IO alone.

Methods and Materials

Data were collected from Canadian Kidney Cancer Information System from January 2011 to September 2019 across 14 academic centers. Patients with mRCC who received IO as first- or second-line therapy were included. RT was categorized as radical dose or palliative dose. Kaplan-Meier estimates were reported for overall survival (OS) and time to treatment failure. Cox proportional hazard models were used adjusted for age and International Metastatic RCC Database Consortium risk categories.

Results

In total, 505 patients were included in the study: 179 received RT + IO and 326 received IO alone. Two-year OS for the RT + IO group was 55.0% compared with 66.4% in the IO alone cohort (adjusted hazard ratio [aHR], 1.38; P = .07). At 2 years, 12.2% of the RT + IO patients remained on therapy versus 30.9% in the IO alone group (aHR, 1.30; P = .02). For patients receiving first-line therapy, 2-year OS in the RT + IO group was 56.4% versus 78.4% in the IO alone arm, though this difference was not statistically significant (aHR, 1.23; P = .56). For patients receiving radical dose and palliative dose, 2-year OS was 57.0% and 53.9%, respectively (aHR, 0.86; P = .63).

Conclusions

In this descriptive analysis, more than one-third of patients with mRCC received RT and demonstrated inferior outcomes compared with IO alone. Potential explanations include greater presence of adverse metastatic sites in those receiving RT. Prospective clinical trials evaluating potential benefits of RT in an IO era remain an important need.

Evolving landscape of first-line combination therapy in advanced renal cancer: a systematic review

Background:

Renal cell carcinoma (RCC) is a common malignancy with approximately 30% of cases diagnosed at the advanced or metastatic stage. While single-agent vascular endothelial growth factor-targeted therapy has been a mainstay of treatment, data from multiple phase III trials assessing first-line immune checkpoint inhibitor (ICI) combinations have demonstrated a significant survival benefit.

Methods:

A systematic search of the published and presented literature was performed to identify phase III trials assessing ICI combination regimens in RCC using search terms ‘immune checkpoint inhibitors’ AND ‘renal cell carcinoma,’ AND ‘advanced’.

Results:

Six phase III trials showed significant benefits for ICI combinations compared with sunitinib. Nivolumab plus ipilimumab significantly improved overall survival [OS; median, 47.0 versus 26.6 months, hazard ratio (HR) = 0.68, 95% confidence interval (CI) = 0.58–0.81, p < 0.0001) and progression-free survival (PFS; median 11.6 versus 8.3 months, HR = 0.73, 95% CI = 0.61–0.87, p = 0.0004) in International Metastatic renal cell carcinoma Database Consortium intermediate and poor-risk patients. OS was also significantly improved for ICI plus tyrosine kinase inhibitor combinations regardless of risk, including pembrolizumab plus either axitinib (HR = 0.73, 95% CI = 0.60–0.88, p < 0.001) or lenvatinib (HR = 0.66, 95% CI = 0.49–0.88, p = 0.005) and nivolumab plus cabozantinib (HR = 0.66, 95% CI = 0.50–0.87, p = 0.003). No new safety signals were identified.

Conclusions:

Phase III first-line trials of ICI combinations showed survival benefits compared with a control arm of sunitinib. Global access to these combinations should be made available to patients with advanced RCC.

Imaging Response to Contemporary Immuno-oncology Combination Therapies in Patients With Metastatic Renal Cell Carcinoma

IMPORTANCE

The association between treatment with first-line immuno-oncology (IO) combination therapies and physician-assessed objective imaging response among patients with metastatic renal cell carcinoma (mRCC) remains uncharacterized.

OBJECTIVE

To compare the likelihood of objective imaging response (ie, complete or partial response) to first-line IO combination ipilimumab-nivolumab (IOIO) therapy vs approved IO with vascular endothelial growth factor inhibitor (IOVE) combination therapies among patients with mRCC.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter international cohort study was nested in routine clinical practice. A data set from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) was used to identify consecutive patients with mRCC who received treatment with IO combination therapies between May 30, 2013, and September 9, 2021. A total of 899 patients with a histologically confirmed diagnosis of mRCC who received treatment with a first-line IOVE or IOIO regimen and had evaluable responses were included.

EXPOSURES

Best overall response to first-line IO combination therapy based on Response Evaluation Criteria in Solid Tumors, version 1.1.

MAIN OUTCOMES AND MEASURES

The primary outcome was the difference in treating physician-assessed objective imaging response based on the type of first-line IO combination therapy received. Secondary outcomes included the identification of baseline characteristics positively associated with objective imaging response and the association of objective imaging response with overall survival.

RESULTS

Among 1085 patients with mRCC who received first-line IO combination therapies, 899 patients (median age, 62.8 years [IQR, 55.9-69.2 years]; 666 male [74.2%]) had evaluable responses. A total of 794 patients had information available on IMDC risk classification; of those, 127 patients (16.0%) had favorable risk, 442 (55.7%) had intermediate risk, and 225 (28.3%) had poor risk. With regard to best overall response among all participants, 37 patients (4.1%) had complete response, 344 (38.3%) had partial response, 315 (35.0%) had stable disease, and 203 (22.6%) had progressive disease. Corresponding median overall survival was not estimable (95% CI, 53.3 months to not estimable) among patients with complete response, 55.9 months (95% CI, 44.1 months to not estimable) among patients with partial response, 48.1 months (95% CI, 33.4 months to not estimable) among patients with stable disease, and 13.0 months (95% CI, 8.4-18.1 months) among patients with progressive disease (log rank P < .001). Treatment with IOVE therapy was found to be independently associated with an increased likelihood of obtaining response (OR, 1.89; 95% CI, 1.26-2.81; P = .002) compared with IOIO therapy. The presence of lung metastases (odds ratio [OR], 1.49; 95% CI, 1.01-2.20), receipt of cytoreductive nephrectomy (OR, 1.59; 95% CI, 1.04-2.43), and favorable IMDC risk (OR, 1.93; 95% CI, 1.10-3.39) were independently associated with an increased likelihood of response.

CONCLUSIONS AND RELEVANCE

In this study, treatment with IOVE therapy was associated with significantly increased odds of objective imaging response compared with IOIO therapy. The presence of lung metastases, receipt of cytoreductive nephrectomy, and favorable IMDC risk were associated with increased odds of experiencing objective imaging response. These findings may help inform treatment selection, especially in clinical contexts associated with high-volume multisite metastatic disease, in which obtaining objective imaging response is important.

Patterns of care for non‐metastatic castration‐resistant prostate cancer: A population‐based study

Objectives

To describe patterns of practice of PSA testing and imaging for Ontario men receiving continuous ADT for the treatment of non‐metastatic castration‐resistant prostate cancer (nmCRPC).

Patients and Methods

This was a retrospective, longitudinal, population‐based study of administrative health data from 2008 to 2019. Men 65 years and older receiving continuous androgen deprivation therapy (ADT) with documented CRPC were included. An administrative proxy definition was applied to capture patients with nmCRPC and excluded those with metastatic disease. Patients were indexed upon progression to CRPC and were followed until death or end of study period to assess frequency of monitoring with PSA tests and conventional imaging. A 2‐year look‐back window was used to assess patterns of care leading up to CRPC as well as baseline covariates.

Results

At a median follow‐up of 40.1 months, 944 patients with nmCRPC were identified. Their median time from initiation of continuous ADT to CRPC was 26.0 months. 60.7% of patients had their PSA measured twice or fewer in the year prior to index, and 70.7% patients did not receive any imaging in the year following progression to CRPC. Throughout the study period, 921/944 (97.6%) patients with CRPC progressed to high‐risk (HR‐CRPC) with PSA doubling time ≤ 10 months, of which more than half received fewer than three PSA tests in the year prior to developing HR‐CRPC, and 30.9% received no imaging in the subsequent year.

Conclusion

PSA testing and imaging studies are underutilized in a real‐world setting for the management of nmCRPC, including those at high risk of developing metastatic disease. Infrequent monitoring impedes proper risk stratification, disease staging and detection of treatment failure and/or metastases, thereby delaying the necessary treatment intensification with life‐prolonging therapies. Adherence to guideline recommendations and the importance of timely staging should be reinforced to optimize patient outcomes.

Predictors of objective response to first-line immuno-oncology combination therapies in metastatic renal cell carcinoma: Results from the international metastatic renal cell database consortium (IMDC)

310

Background: Predictors of objective response to first-line (1L) immuno-oncology (IO) combination therapies remain elusive. We sought to characterise clinical variables and their association with investigator assessed best overall response. Methods: Using the IMDC, we retrospectively identified patients treated with 1L ipilimumab nivolumab (IPI-NIVO) or approved IO/vascular endothelial growth factor (VEGF) inhibitor combinations (IOVE). Patients were classified, per RECIST v1.1, as responders (complete or partial response (CR or PR)) or non-responders (stable or progressive disease (SD or PD)). Logistic regression was used to adjust for IMDC criteria. Results: Out of 1084 patients, 794 (73%) received IPI-NIVO and 290 (27%) received IOVE (axitinib+pembrolizumab, cabozantinib+nivolumab, axitinib+avelumab, lenvatinib+pembrolizumab). Favourable, intermediate and poor IMDC risk comprised 147 (16%), 517 (55%) and 272 (29%) respectively. Of the 898 patients with evaluable responses, 37 (4%) achieved a best response of CR, 343 (38%) PR, 315 (35%) SD and 203 (23%) PD. Corresponding median overall survival from time of 1L initiation was: not reached, 55.9, 48.1, and 13 months respectively (logrank p < 0.0001). In a multivariable model, lung metastases and cytoreductive nephrectomy (CN) (performed after diagnosis of metastatic disease and before 1L therapy) retained independent association with response, after adjustment for IMDC criteria. Factors not associated with response included (with univariable p values): gender (p = 0.58), age (p = 0.06), sarcomatoid histology (p = 0.99), smoking status (p = 0.39), liver (p = 0.63) and brain (p = 0.12) metastases. As in the VEGF monotherapy era, improved IMDC prognostic risk was associated with response. Results were similar when restricted to the IPI-NIVO cohort. Conclusions: Presence of lung metastases, CN and better IMDC risk group are associated with a higher probability of response to 1L immunotherapy combination regimens. Further work to identify reliable predictors of response to guide treatment selection and patient counselling is warranted.[Table: see text]

Characterizing IMDC prognostic groups in contemporary first-line combination therapies for metastatic renal cell carcinoma (mRCC)

308

Background: The combination of immuno-oncology agents (IO) ipilimumab and nivolumab (IPI-NIVO) and combinations of IO with vascular endothelial growth factor targeted therapies (IOVE) have demonstrated efficacy in clinical trials for the first-line treatment of mRCC. This study seeks to establish real-world clinical benchmarks based on the International mRCC Database Consortium (IMDC) criteria using vascular endothelial growth factor targeted therapy (VEGF-TT) treated patients for context. Methods: The IMDC database (IMDConline.com) was used to identify patients with mRCC who received first-line IPI-NIVO, IOVE (axitinib/pembrolizumab, lenvatinib/pembrolizumab, cabozantinib/nivolumab, or axitinib/avelumab) and VEGF-TT (sunitinib or pazopanib) from 2002-2021. The primary endpoint was overall survival (OS) and was calculated from time of initiation of first-line therapy to death or last follow up. Log-rank tests were conducted to compare favorable, intermediate, and poor risk OS outcomes within treatment groups. Overall response rates (ORR) and complete response (CR) rates were calculated based on physician assessment of best clinical response. Results: In total, 692 patients received IPI-NIVO, 244 received IOVE, and 7152 received VEGF-TT. Baseline characteristics for IPI-NIVO, IOVE, and VEGF-TT, respectively, were as follows: median age (interquartile range) 63 (56-69), 64 (57-70), and 63 (56-70); male 72%, 74%, and 72% (p=0.74); non-clear cell histology 15%, 10%, and 13% (p=0.15); sarcomatoid features 24%, 15%, and 13% (p<0.0001); brain metastasis 8%, 4%, and 8% (p=0.04); liver metastasis 18%, 14%, and 18% (p=0.17); underwent nephrectomy 61%, 79% and 80% (p<0.0001). OS and ORR are reported in the table. P-values (log rank) for OS between risk groups were significant for IPI-NIVO (p<0.0001), IOVE (p=0.0005), and VEGF-TT (p<0.0001). Conclusions: These findings provide real-world survival and response benchmarks for contemporary first-line mRCC treatments and could be helpful for patient counselling. In addition, these findings mirror the efficacy of combination therapies established in clinical trials against VEGF-TT monotherapy. IMDC criteria continue to risk stratify patients in these novel combination therapies.[Table: see text]

Comparison of patients with high-risk nonmetastatic clear cell renal carcinoma in adjuvant therapy trials versus nonclinical trial patients

361

Background: Characteristics of patients with high risk for recurrence non-metastatic renal cell carcinoma (nmRCC) participating in adjuvant therapy clinical trials post-nephrectomy have not been well described. We evaluated high risk nmRCC patients in the CKCis database to explore differences between trial and non-trial patients. Methods: Adult patients undergoing partial or radical nephrectomy for clear cell nmRCC between January 1, 2011 and March 31, 2021 were included. CKCis is a prospective cohort of patients from 14 Canadian academic institutions. Patients with high risk nmRCC (using modified UCLA Integrated Staging System) were included. Demographic, clinical, and survival statistics were analyzed for all patients and comparatively for the trial and non-trial groups. Results: 1459 patients, including 63 in adjuvant trials, were evaluated. 71% were male, 91% had pT3N0M0 disease. Disease characteristics including tumor size, stage, grade, location, necrosis, and margin status were similar between groups. Trial patients were younger (mean age 58.1 vs. 63.6; p < 0.0001) and had lower Charlson Comorbidity Index scores (median 4 [3,6) vs. 5 [4,6] p < 0.001). Estimated overall survival (OS) at 5 years was 80.8% (95% CI, 65,90) for trial patients and 74.8% (95% CI, 71,78.2) for non-trial patients. Recurrence-free survival at 5 years for trial patients was 48.6% (95% CI, 34,61.7) and 39.2% (95% CI, 35.2,43.1) for non-trial patients. Conclusions: Patients in adjuvant trials were younger and healthier at baseline than the average high risk nmRCC CKCis patient. Trial patients appear to have had longer time to recurrence and longer survival compared to non-trial patients, although not reaching statistical significance. Selection bias is common in clinical trials and evaluation of real-world population-based evidence of patients receiving adjuvant therapy will be important to ensure phase 3 trial results have external validity.

Effectiveness of first-line therapy in patients with advanced non-clear renal cell carcinoma (nccRCC)

304

Background: Current treatment principles for advanced nccRCC have been largely extrapolated from guidelines for clear cell RCC. Given the emerging randomized data for select nccRCC subtypes, real-world outcomes for these patients are informative particularly in the contemporary checkpoint inhibitor era. Methods: We performed an analysis using the Canadian Kidney Cancer information system (CKCis), a prospective database involving 14 academic centers, on nccRCC patients undergoing first-line systemic therapy between January 2011 – December 2019. Treatment groups were defined as receipt of: vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGF-TKI), mammalian target of rapamycin inhibitors (mTORi), and PD-1/PD-L1 immune checkpoint inhibitors (ICI, mono- or combination therapy). Primary outcome was 1-yr overall survival (OS) rate. Secondary outcomes were median time to treatment failure ((TTF, months), defined as treatment discontinuation, change or death) and objective response rate (ORR, %). Results: We identified 265 nccRCC patients: 204 (77.0%) received VEGF-TKI, 19 (7.2%) received mTORi and 42 (15.8%) received ICI-based first-line therapy (Table). Overall, median age was 64 years, 75% were male, 84% were classified as IMDC intermediate/poor risk, and 16% underwent prior nephrectomy. Twenty-three percent of patients were enrolled in clinical trials. Patients received primarily sunitinib (81%) or pazopanib (15%) in the VEGF-TKI group (other: 4%), while mTORi-treated patients received temsirolimus (74%) or everolimus (26%). For the ICI-based treatment group, most patients received combination therapy as ipilimumab-nivolumab (71%) or pembrolizumab-axitinib (26%), with 3% receiving ICI monotherapy. 1-yr OS was 65.2% for VEGF-TKI, 57.9% for mTORi and 69.0% for ICI-treated patients. Median TTF was 3.3 for VEGF-TKI, 3.5 for mTORi and 7.1 mos for ICI-treated patients. ORR was 17%, 5%, and 37% respectively for the VEGF-TKI, mTORi and ICI-treated groups. Conclusions: We describe the effectiveness of first-line therapy for patients with nccRCC from a national database. This real-world data suggests an association between first-line ICI-based therapies and improved outcomes, albeit with cabozantinib not available for the indication during this time. Our data supports consensus recommendations for preferred use of ICI-based or VEGF-TKI over mTORi as first-line therapy in nccRCC.[Table: see text]

Efficacy of tyrosine kinase inhibitors (TKI) after combination ipilimumab plus nivolumab (I/N) in metastatic clear cell renal cell carcinoma (ccmRCC) patients: Results from the Canadian Kidney Cancer Information System (CKCis)

346

Background: The use of I/N is a proven first-line option for patients with intermediate/poor IMDC prognostic criteria. The use of vascular endothelial growth factor inhibitors such as sunitinib have shown activity in the treatment of ccmRCC, but their effectiveness post I/N needs better characterization. This study aims to demonstrate the efficacy of sunitinib, and other TKI agents post I/N in ccmRCC in a real world setting. Methods: Patients with ccmRCC who had received I/N and were subsequently treated with TKI between Jan 1, 2011 and December 31, 2019 were identified from CKCis. Time to treatment failure (TTF – time from start of first subsequent TKI to discontinuation for any reason) and overall survival (OS) – time from first subsequent TKI to death) were calculated using the Kaplan-Meier method. Cox regression was performed to adjust for IMDC criteria. RECIST criteria was used to determine best overall response (ORR) of TKI radiographically. Results: 64 patients were treated with TKI post I/N. Characteristics and outcomes are listed in the table. Of the second-line TKI patients, 51 received sunitinib, 10 received pazopanib and 3 received other TKI. Reasons for second-line TKI discontinuation are: 28% toxicity, 34% progression, 7% other reasons while 31% remain on treatment. Median follow-up time was 12.9m. ORR for second-line TKI overall and second-line sunitinib was 30.0% and 29.4%, respectively. Conclusions: These data show that TKI are active after I/N in ccmRCC. TTF may underestimate PFS due to the large number of patients discontinuing treatment for toxicity and not progression. Efficacy of second-line TKI post I/N in this dataset is similar that of first-line sunitinib from recent randomized phase III trials, suggesting that there may be no significant loss of TKI activity after having received first-line I/N. Overall, these data support the use of TKI after I/N.[Table: see text]

Association of cabozantinib dose reductions for toxicity with clinical effectiveness in metastatic renal cell carcinoma (mRCC): Results from the Canadian Kidney Cancer Information System (CKCis)

316

Background: Cabozantinib (cabo) is an oral multi-targeted tyrosine kinase inhibitor (TKI) with activity in mRCC. TKI toxicity, an indicator of adequate drug exposure, has been associated with clinical effectiveness for sunitinib, pazopanib, and axitinib. We explored whether cabo dose reductions (a surrogate for toxicity) were associated with improved clinical outcomes in mRCC. Methods: Using the CKCis database, we performed an analysis of patients treated with cabo in the second-line or later between 2011-2021. We divided the cohort into those needing a dose reduction (DR, defined as less than the starting dose at time of treatment discontinuation) and those who did not (no-DR). We compared outcomes by dose reduction status, including objective response rate (ORR), time to treatment failure (TTF), and overall survival (OS). Results: We identified 260 patients who received cabo, of which 103 (41.0%) needed a DR. Across all lines, the ORR was similar between the DR and non-DR groups: 19.6% vs. 18.9% (p = 0.903) respectively. The median TTF was 12.75 months (95% CI 10.38 – 17.64) in the DR group vs. 6.44 months (95% CI 5.49 – 8.67) in the no-DR group. After adjusting for IMDC risk, the hazard ratio (HR) for TTF comparing DR vs. no-DR was 0.69 (95% CI 0.50 - 0.97, p-value = 0.03). The median OS was 29.6 months (95% CI 19.58 – 42.64) in the DR group vs. 15.28 (95% CI 11.04 – 22.64) in the no-DR group. After adjusting for IMDC risk, the HR for OS comparing DR vs. no-DR was 0.65 (95% CI 0.43 - 0.98, p = 0.04). Conclusions: Cabozantinib dose reductions, a surrogate for toxicity and adequate drug exposure, appear to be associated with improved TTF and OS in mRCC. Toxicity driven/individualized dosing strategies for cabo alone and in combination with immunotherapy, warrant further investigation.[Table: see text]

Patterns of care for patients with non-metastatic castration-resistant prostate cancer: Population-based study in Ontario, Canada

53

Background: To describe patterns of practice of PSA testing and imaging for Ontario men receiving continuous androgen deprivation therapy (ADT) for the treatment of non-metastatic castration-resistant prostate cancer (nmCRPC). Methods: This was a retrospective, longitudinal, population-based study of administrative health data from 2008 to 2019. Men > 65 years old receiving continuous ADT with documented CRPC were included. An administrative proxy definition was applied to capture patients with nmCRPC patients and excluded those with metastatic disease. Patients were indexed upon progression to CRPC and were followed until death or end of study period to assess frequency of monitoring with PSA tests and conventional imaging. A 2-year look-back window was used to assess patterns of care leading up to CRPC, as well as baseline covariates. Results: At a median follow-up of 40 months, 944 patients with CRPC were identified. Their median time from initiation of ADT to CRPC was 26 months, 61% of patients had their PSA measured twice or fewer in the year prior to index and 71% patients did not receive any imaging in the year following progression to CRPC. Almost all patients (98%, n = 921/944) in the study progressed to high-risk CRPC (HR-CRPC) during the study period, of which more than half received fewer than 3 PSA tests in the year prior to progression to HR-CRPC, and 31% received no imaging in the subsequent year. Conclusions: PSA testing and imaging studies are under-utilized in a real-world setting for the management of nmCRPC, including those at high-risk of developing metastatic disease. Infrequent monitoring impedes proper risk stratification, disease staging, detection of treatment failure and/or metastases, likely delaying necessary treatment intensification with life-prolonging therapies. Adherence to guideline recommendations and the importance of timely staging should be reinforced to optimize patients’ outcome.

Real-World Use of Androgen-Deprivation Therapy: Intensification Among Older Canadian Men With de Novo Metastatic Prostate Cancer

BACKGROUND

Despite the wealth of evidence demonstrating the efficacy of treatment intensification beyond androgen-deprivation therapy (ADT) among patients with de novo metastatic castration-sensitive prostate cancer (mCSPC), little is known of its real-world use. This study examined the real-world uptake of ADT treatment intensification among older men in a large Canadian province.

METHODS

We performed a retrospective population-based cohort study using province-wide linked administrative data in Ontario, Canada. Patients 66 years of age and older with de novo mCSPC were included and their treatment with conventional ADT-based regimens, ADT plus next-generation androgen receptor axis-targeted therapy, and ADT plus docetaxel were identified and stratified by time.

RESULTS

From 2014 to 2019, 3556 patients were identified with de novo mCSPC. Most patients (n = 2794 [78.6%]) were treated with a conventional ADT regimen, whereas 399 (11.2%) patients received ADT intensification with docetaxel and 52 (1.5%) patients received abiraterone acetate plus prednisone. In a time-stratified analysis of ADT intensification before and after the pivotal AA+P trial (LATITUDE), AA+P uptake increased from 0.5% to 3.0%, whereas docetaxel use dropped from 12.0% to 10.0%. The median survival of the study population was 18 months (interquartile range = 10-31).

CONCLUSIONS

The majority of patients with de novo mCSPC are treated with ADT alone in the Canadian real-world setting, despite randomized clinical trial evidence of benefit with the use of ADT-intensified regimens. As ADT treatment intensification is substantially underused, better understanding of the barriers to treatment and targeted education to address them are needed.

Results from a Canadian consensus forum of key controversial areas in the management of advanced prostate cancer: Recommendations for Canadian healthcare providers

INTRODUCTION

Rapid progress in diagnostics and therapeutics for the management of prostate cancer (PCa) have created areas where high-level evidence to guide practice is lacking. The Genitourinary Research Consortium (GURC) conducted its second Canadian consensus forum to address areas of controversy in the management of PCa and provide recommendations to guide treatment.

METHODS

A panel of PCa specialists discussed topics related to the management of PCa. The core scientific committee finalized the design, questions and the analysis of the consensus results. Attendees then voted to indicate their management choice regarding each statement/topic. Questions for voting were adapted from the 2019 Advanced Prostate Cancer Consensus Conference. The thresholds for agreement were set at ≥ 75% for 'consensus agreement', > 50% for "near-consensus", and ≤ 50% for "no consensus".

RESULTS

The panel was comprised of 29 PCa experts including urologists (n=12), medical oncologists (n= 12), and radiation oncologists (n= 5). Voting took place for 65 pre-determined questions and three ad hoc questions. Consensus was reached for 34 questions, spanning a variety of areas including biochemical recurrence, treatment of metastatic castration-sensitive PCa, management of non-metastatic and metastatic castration-resistant PCa, bone health, and molecular profiling.

CONCLUSION

The consensus forum identified areas of consensus or near-consensus in more than half of the questions discussed. Areas of consensus typically aligned with available evidence, and areas of variability may indicate a lack of high-quality evidence and point to future opportunities for further research and education.

Active Surveillance in Metastatic Renal Cell Carcinoma: Results From the Canadian Kidney Cancer Information System

BACKGROUND

Active surveillance (AS) is a commonly used strategy in patients with slow-growing disease. We aimed to assess the outcomes and safety of AS in patients with metastatic renal cell carcinoma (mRCC).

PATIENTS AND METHODS

We used the Canadian Kidney Cancer information system (CKCis) to identify patients with mRCC diagnosed between January 1, 2011, and December 31, 2016. The AS strategy was defined as (1) the start of systemic therapy ≥ 6 months after diagnosis of mRCC, or (2) never receiving systemic therapy for mRCC with an overall survival (OS) of ≥1 year. Patients starting systemic treatment <6 months after diagnosis of mRCC were defined as receiving immediate systemic treatment. OS and time until first-line treatment failure (TTF) were compared between the two cohorts.

RESULTS

A total of 853 patients met the criteria for AS (cohort A). Of these, 364 started treatment >6 months after their initial diagnosis (cohort A1) and 489 never started systemic therapy (cohort A2); 827 patients received immediate systemic treatment (cohort B). The 5-year OS probability was significantly greater for cohort A than for cohort B (70% vs. 33.6%; P < .0001). After adjusting for International Metastatic RCC Database Consortium risk criteria and age, both OS (hazard ratio [HR] = 0.58; 95% confidence interval [CI], 0.47-0.70; P < .0001) and TTF (HR = 0.72; 95% CI, 0.60-0.85; P = .0002) were greater in cohort A1 compared with B. For cohort A1, the median time on AS was 14.2 months (range, 6-71).

CONCLUSIONS

Based on the largest analysis of AS in mRCC to date, our data suggest that a subset of patients may be safely observed without immediate initiation of systemic therapy.

Outcomes of patients with solid tumour malignancies treated with first-line immuno-oncology agents who do not meet eligibility criteria for clinical trials

BACKGROUND

Immuno-oncology (IO)-based therapies have been approved based on randomised clinical trials, yet a significant proportion of real-world patients are not represented in these trials. We sought to compare the outcomes of trial-ineligible vs. -eligible patients with advanced solid tumours treated with first-line (1L) IO therapy.

PATIENTS AND METHODS

Using the International Metastatic Renal Cell Carcinoma (RCC) Database Consortium and the Alberta Immunotherapy Database, patients with advanced RCC, non-small-cell lung cancer (NSCLC) or melanoma treated with 1L PD-(L)1 inhibition-based therapy were included. Trial eligibility was retrospectively determined as per commonly used exclusion criteria. The outcomes of interest were overall survival (OS), overall response rate (ORR), treatment duration (TD) and time to next treatment (TTNT).

RESULTS

A total of 395 of 1241 (32%) patients were deemed trial-ineligible. The main reasons for ineligibility based on preselected exclusion criteria were Karnofsky performance status <70%/Eastern Cooperative Oncology Group performance status >1 (40%, 158 of 395), brain metastases (32%, 126 of 395), haemoglobin < 9 g/dL (16%, 63 of 395) and estimated glomerular filtration rate <40 mL/min (15%, 61 of 395). Between the ineligible vs. eligible groups, the median OS, ORR, median TD and median TTNT were 10.2 vs. 39.7 months (p < 0.01), 36% vs. 47% (p < 0.01), 2.7 vs. 6.9 months (p < 0.01) and 6.0 vs. 16.8 months (p < 0.01), respectively. Subgroup analyses showed statistically significant inferior OS, TD and TTNT for trial-ineligible vs. -eligible patients across all tumour types. Adjusted hazard ratios for death in RCC, NSCLC and melanoma were 1.84 (95% confidence interval [CI] 1.22-2.77), 2.21 (95% CI 1.58-3.11) and 1.82 (95% CI 1.21-2.74), respectively..

CONCLUSIONS

Thirty-two percent of real-world patients treated with contemporary 1L IO-based therapies were ineligible for clinical trials. Although one-third of the trial-ineligible patients responded to treatment, the overall trial-ineligible population had inferior outcomes than trial-eligible patients. These data may guide patient counselling and temper expectations of benefit.

Real-Word Experience of Cabozantinib in Metastatic Renal Cell Carcinoma (mRCC): Results from the Canadian Kidney Cancer information system (CKCis)

BACKGROUND: Cabozantinib is an oral multitargeted tyrosine kinase inhibitor (TKI) that has demonstrated efficacy in metastatic renal-cell carcinoma (mRCC) randomized trials. OBJECTIVE: To explore the real-world effectiveness of cabozantinib in pretreated patients with mRCC, including patients who progressed on immune-oncology checkpoint inhibitor (ICI) therapy. METHODS: Using the Canadian Kidney Cancer information system (CKCis), patients with mRCC treated with cabozantinib monotherapy as second-line or later from January 1, 2011 to September 1, 2019 were identified. Patients were stratified based on line of cabozantinib received. We reported overall survival (OS), time to treatment failure (TTF) and disease control rate (DCR). Prognostic variables were analyzed using multivariable analysis. RESULTS: 157 patients received cabozantinib (median TTF 8.0 months; median OS 15.8 months): 37 (24%) in the second line (median TTF 10.4 months; median OS 18.9 months) 66 (42%) in third line (median TTF 5.9 months; median OS 13.3 months) and 54 (34%) in either 4th or 5th line (median TTF 9.4 months; median OS 16.8 months). One hundred sixteen patients (74%) received cabozantinib after prior ICI therapy (median TTF of 7.6 months; median OS of 15.8 months). DCR in all patients was 63% with 46%, 65% and 72% in 2nd line, 3rd line and 4th/5th line patients respectively. DCR in patients who received cabozantinib after prior ICI therapy was 64%. CONCLUSIONS: Cabozantinib is effective in a real-world, unselected population of mRCC patients, including in those who have progressed on prior ICI therapy, and in those exposed to multiple lines of therapy.

Prognostic association between common laboratory tests and overall survival in men with de novo metastatic castration-sensitive prostate cancer: A population-based study

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Background: Despite significant advancements in the treatment of metastatic prostate cancer, a validated prognostic tool for patients with de novo metastatic castration-sensitive prostate cancer (mCSPC) is still lacking. Using population-based data from Ontario, Canada, we sought to examine the prognostic association between common laboratory tests and survival for patients with mCSPC. Methods: A population-based cohort of men aged 66 years and older diagnosed with de novo metastatic prostate cancer between 2014-2019 were included. We assessed the association between laboratory tests at the time of cancer diagnosis and overall survival (OS). Utilizing a complete case analysis, we used Cox proportional hazards models to assess the association between these laboratory tests and OS while adjusting for patient and disease characteristics. Results: A total of 3,556 men with de novo mCSPC were included. On multivariable analysis, there were significant associations between OS and neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, albumin, hemoglobin, PSA decrease and PSA nadir <0.1 ng/mL (please see table). Conclusions: Commonly available laboratory tests provide important prognostic information for patients with newly diagnosed mCSPC given demonstrated associations to overall survival. Apart from PSA kinetics, none of these baseline tests were performed in more than 57% of patients indicating underutilization of these low-cost prognostic biomarkers. [Table: see text]

Geographic variation in systemic therapy in men age 66 years and older with de novo metastatic castration-sensitive prostate cancer: A population-based study in a single payer health-system

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Background: Significant developments in the standard of care for patients with de novo metastatic castration-sensitive prostate cancer (mCSPC) have been reported over the past decade. Treatment intensification with systemic therapies in addition to androgen deprivation therapy (ADT) alone is guideline recommended for most patients. We studied the geographic variation in the use of systemic therapy for de novo mCSPC in Ontario, Canada, a single-payer health system. Methods: We performed a population-based study of men aged 66 years and older diagnosed with de novo mCSPC between 2014-2019. We linked population-based healthcare databases, as administered at the level of Local Health Integration Networks (LHINs) in Ontario, to examine treatment patterns following diagnosis of de novo mCSPC. We categorized initial mCSPC treatments as those begun within 60 days preceding and 6 months following diagnosis and examined the proportion of patients receiving LHRH alone, first generation anti-androgen (AA) alone, combined androgen blockade (CAB; LHRH + 1st gen AA), ADT + abiraterone acetate + prednisone (AAP), and, ADT + docetaxel (D). In aggregate, we considered LHRH alone, AA alone and CAB as “standard ADT”, and ADT + AAP and ADT + D as “ADT-plus”. Multinomial logistic regression analyses were used to examine the association between receiving systemic treatment intensification (“ADT-plus”) or no prostate cancer pharmacotherapy relative to ADT across geographic regions, while adjusting for baseline patient and disease characteristics. Results: We identified 3,556 men over 66 with de novo mCSPC. Overall, 2794 (78.6%) received standard ADT, 311 (8.7%) did not receive prostate cancer-directed pharmacotherapy, and 451 patients (12.7%) of patients received “ADT-plus”. Utilization of AAP increased from 0.5% to 3% following the LATITUDE data release in 2017, while D decreased from 12% to 10%. There was significant variation in treatment strategies between geographic regions in use of “ADT-plus” ranging from 7 to 20% (p < 0.0001), a difference which persisted after accounting for patient demographics, comorbidity, rurality, and disease characteristics (p = 0.036). Conclusions: Despite proven survival benefits in randomized controlled trials, intensified treatment with docetaxel or abiraterone in addition to ADT was infrequently utilized in this population-based study of men age 66 years and over with mCSPC.

Real-world utilization of docetaxel among men with de novo metastatic castration-sensitive prostate cancer: A population-based study in men aged 66 or older

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Background: Docetaxel was the first agent, when added to androgen deprivation therapy (ADT), to demonstrate a survival benefit in men with metastatic castration-sensitive prostate cancer (mCSPC). It remains an important guideline recommendation approach in these men. However, real-world experience among patients with de novo metastatic disease is poorly understood. Using population-based data from Ontario Canada, we examined the real-world experience of using docetaxel in mCSPC. Methods: Men aged 66 years and older diagnosed with de novo metastatic prostate cancer between 2014-2019 were captured. The Cancer Activity Level Reporting system tracks information regarding the use of cancer treatments, including details of systemic therapy. We identified patients who received docetaxel intensification to ADT following diagnosis of de novo mCSPC and analyzed the proportion of patients who completed 6 cycles of treatment, required a dose decrease, and who visited the emergency department (ED) or were hospitalized for febrile neutropenia. Results: Over the 5-year study period, 399 men received docetaxel treatment among 3,556 identified with de novo mCSPC. The median age was 72 (IQR 68-76) and mean Charlson comorbidity index was 0.15 (SD +/- 0.72). Of the 399 men, 230 (58%), 202 (51%) and 175 (44%) patients completed at least 4, 5 and 6 cycles of docetaxel, respectively. Dose reduction during docetaxel treatment was required in 173 (43%) patients. Filgrastim was prescribed among 29 (7.3%) patients. Hospitalization or ED visit for febrile neutropenia was observed in 63 (16 %) of patients who received docetaxel. Conclusions: Among men age 66 years and over who received docetaxel and ADT for mCSPC, less than half were able to complete all six prescribed cycles. In addition, over two fifth required dose reductions and 16% experienced febrile neutropenia requiring hospitalization or ED visit. These data highlight the differences in expected outcomes between clinical trial populations (as reported in CHAARTED) and routine use.

Prognostic impact of paraneoplastic syndromes on patients with non-metastatic renal cell carcinoma undergoing surgery: Results from Canadian Kidney Cancer information system

INTRODUCTION

The impact of paraneoplastic syndromes (PNS) on survival in patients with renal cell carcinoma (RCC) is uncertain. This study was conducted to analyze the association of PNS with recurrence and survival of patients with non-metastatic RCC undergoing nephrectomy.

METHODS

The Canadian Kidney Cancer information system is a multi-institutional cohort of patients started in January 2011. Patients with nephrectomy for non-metastatic RCC were identified. PNS included anemia, polycythemia, hypercalcemia, and weight loss. Associations between PNS and recurrence or death were assessed using Kaplan-Meier curves and multivariable analysis.

RESULTS

Of 4337 patients, 1314 (30.3%) had evidence of one or more PNS. Patients with PNS were older, had higher comorbidity, and had more advanced clinical and pathological tumor characteristics as compared to patients without PNS (all p<0.05). Kaplan-Meier five-year estimated recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were significantly worse in patients with PNS (63.7%, 84.3%, and 79.6%, respectively, for patients with PNS vs. 73.9%, 90.8%, and 90.1%, respectively, for patients without PNS, all p<0.005). On univariable analysis, presence of PNS increased risk of recurrence (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.48-1.90, p<0.0001) and cancer-related death (HR 1.85, 95% CI 1.34-2.54, p=0.0002). Adjusting for known prognostic factors, PNS was not associated with recurrence or survival.

CONCLUSIONS

In non-metastatic RCC patients undergoing surgery, presence of PNS is associated with older age, higher Charlson comorbidity index score, advanced tumor stage, and aggressive tumor histology. Following surgery, baseline PNS is not strongly independently associated with recurrence or death.

Current Management of Localized Muscle-Invasive Bladder Cancer: A Consensus Guideline from the Genitourinary Medical Oncologists of Canada

BACKGROUND: Despite recent advances in the management of muscle-invasive bladder cancer (MIBC), treatment outcomes remain suboptimal, and variability exists across current practice patterns. OBJECTIVE: To promote standardization of care for MIBC in Canada by developing a consensus guidelines using a multidisciplinary, evidence-based, patient-centered approach who specialize in bladder cancer. METHODS: A comprehensive literature search of PubMed, Medline, and Embase was performed; and most recent guidelines from national and international organizations were reviewed. Recommendations were made based on best available evidence, and strength of recommendations were graded based on quality of the evidence. RESULTS: Overall, 17 recommendations were made covering a broad range of topics including pathology review, staging investigations, systemic therapy, local definitive therapy and surveillance. Of these, 10 (59% ) were level 1 or 2, 7 (41% ) were level 3 or 4 recommendations. There were 2 recommendations which did not reach full consensus, and were based on majority opinion. This guideline also provides guidance for the management of cisplatin-ineligible patients, variant histologies, and bladder-sparing trimodality therapy. Potential biomarkers, ongoing clinical trials, and future directions are highlighted. CONCLUSIONS: This guideline embodies the collaborative expertise from all disciplines involved, and provides guidance to further optimize and standardize the management of MIBC.